Stabilized chlorinated paraffins



Patented Jan. 1, 1952 STABILIZED CHLORINATED PARAFFTN S James M. Church, Tenafly, andErnest W. Johnson, Mountainside, N. J., assignors to Metal &

Thermit Corporation ration oi New Jersey New York, N. Y., a corpo- N Drawing. Application May 4, 1948,

Serial No. 25.07% a Claims. (01. 260-6525) This invention relates to the stabilization of chlorinated parafiins having about 10 to about 40 carbon atoms per molecule with tin hydro: carbon compounds, and to the stabilized product. More particularly, it relates to the stabilization of chlorinated parafiins with tin hydrocarbon compounds having the general formula: RAr4-=Sn,

in which R stands for an alkyl radical, Ar is an aryl radical, Sn, of course, is tin, and a: is a numeral equal to '1, 2, 3 or 4.

The efiiciency and use of chlorinated parafiins of the kind described is hindered in many applications by their tendency to decompose. This tendency renders them objectionable as coating agents for textiles, paper, and other materials, for which use they otherwise have certain advantageous properties. Thus, when applied to textiles as fiameproofing agents, they tendto break down over a period of time, forming hydrogen chloride, which attacks the textile material. The same is true in the case of paper, and in this case there are other disadvantages arising out of the, fact that the chlorinated parafiins areapplied to the paper at elevated temperatures. Not only do the chlorinated paraflins, which must be kept hot for some time prior to'use,'undergo degradation, but the hydrogen chloride formed has a tendency to pit the metal rolls used for applying them to the paper. In addition, paper' coated with them may darken or discolor as a result of the decomposition. According to the invention, chlorinated paraffins may be stabilized for general use by adding to them a small quantity or one or more of the class of] compounds defined above. These compounds are both compatible with the chlorinated "paraflins and do not adversely affect their properties. The compounds include tin tetraalkyls, in which the alkyl group may be methyl, ethyl, propyl, butyl, isobutyl, amyl, etc. or in which the alkyl, group may be mixed, as in dibutyldipropyl tin, tributylethyl tin, etc. The compounds also include mixed alkyl-aryl compounds of tin such as dibutyldiphenyl tin, tributylphenyl tin, etc. The chlorinated parafiins to be stabilized may contain varying amounts of chlorine, ranging from about 1 to about 70% or more. By chlorinated paraifins is meant the lower molecu- -lar weight, non-polymerizable, chlorinated parafiin hydrocarbons having about 10 to about carbon atoms per molecule. The stabilizer may be added thereto in amounts up to about 5% by weight, preferably at least 1%. The stabilizer is 4 then intimately dispersed in the chlorinated parafilns in any suitable way, such as by melting and stirring the mixture, or the chlorinated paraifins and the stabilizer may be dissolved in a low boiling solvent and the solvent later evaporated.

The following examples may illustrate the invention. In each example in Table I, a chlorinated paramn containing about chlorine was melted and heated to various temperatures in order to decompose it. The extent of the decomposition was indicated by the amount ofhydrogen chloride gas evolved, the gas being collected and measured at periodic intervals. In each case, also, at least one other sample of the same amount of the chlorinated parafiin, but containing a stabilizing agent, was heated to the same temperature, and the amount of gas evolved was measured at the same time intervals, as before.

Table I 1101 Gas Evolved, mg.

Time 17 No Stabilizer i BmPhSn-tributylphenyl tin. BmPhiSn-dibut ldiphanyl tin. BmSn-totrabuty tin- 1% nugrmsn 1% BurSn As may be seen, at each temperature level the decomposition of the stabilized chlorinated parafin was effectively retarded by the stabilizingv agent, the eii'ect being particularly pronounced at 150 C.

The following examples in Table II illustrate the effect of various concentrations of thestabilizer. In each case the samples were maintained at 150 C. The chlorinated paraflin contained about 70% chlorine.

In the light of the foregoing description, the following is claimed:

1'. Chlorinatediparafdns ,having about 10 to about 40 "carbon 'atoms per molecule "stabilized with up to about by weight of a tin hydrocarbon compound of the formula RxAl4-xSI1, in

. which R is the butyl radical, Ar is the phenyl radical, Sn is tin, and a: is a whole number equal tolto4. v 2.- Chlorinated paraflms having about 10 to In the third, fourth, seventh and eighth columns of Table II, the dashes indicate that the measurement of gas was' discontinued, the trend in each of these cases having been deemed sumciently established.

The examples in Tables III and IV illustrate the extent to which a chlorinated paraffin of lower chlorine content, namely, about chlorine, may be stabilized. In each table, the results were obtained at a temperature of 150 C. The procedure set forth in connection with Table I was followed in the runs of Table III.

The purpose of Table IV is like that of Table II.

about 40 carbon atoms per molecule stabilized with up to about 5% by weight of butyltriphenyl tin.

3. Chlorinated parafllns having about 10' to about 40 carbon atoms per molecule stabilized with up to about 5% by weight oftet'ra'butyl tin. 4. Chlorinated paraihns having about 10 to" about 40 carbon atoms per molecule stabilized with up to about 5% by weight of tributylphenyl tin.

5. Chlorinated 'paraifins having about 10 to about 40 carbon atoms per molecule stabilized with up to about 5% by weight of dibutyldiphenyl tin.

6. Method of stabilizing chlorinated parafllns" having about 10 to about 40 carbon atoms per molecule which comprises adding to said chlorinated paraflins up to about 5% by weight of a tin hydrocarbon compound of' the formula RIAI'i-ISH, in which R is the'butyl radical, A1

is the phenyl radical, S11 istin, and :n'is' a whole number equal to 1 to 4.

'7. Method according to claim 6 in which said tin hydrocarbon compound isbutyltriphenyl tin;

8. Method according to claim 6- in whichsaidj tin hydrocarbon compound is tetrabutyl'tin.

Table III HCl Gas Evolved, mg.

Exam. No. Time, hrs. 7 Chlorinated Para flin Plus-l No Stabilizer 1% Bu4Sn 1% BuzPhSn' 1 39 11.5 16 2 s1 20 27 3 78 24 33 4 91 so as. 5 101 51 57.

Table 1v' E01 Gas'Evolved, mg.

Chlorinated Paraflln- Plus Following Amounts of BmSn- Exam. No. Time, hrs. 0% 0.5% 1%- 2% 1- '43 27 24- 11-- 2 61 4s 2c 13 3 7s 56 3e 15: 4 s5 64 49 27 While the invention has been described in re-' spect to more or less specific embodiments thereof, it will be appreciated that it is capable of obvious variations without departing from its scope.

9. Method according to claim 6 in which said tin hydrocarbon compound is tributylphenyl tin.

10. Method according to claim 6 in which said tin hydrocarbon compound is dibutyldiphenyl tin.

JAMES M. CHURCH. ERNEST W. JOHNSON.

, REFERENCES CITED The following references are of record in the file of'this patent:

i UNITED STATES PATENTS 

1. CHLORINATED PARAFFINS HAVING ABOUT 10 TO ABOUT 40 CARBON ATOMS PER MOLECULE STABILIZED WITH UP TO ABOUT 5% BY WEIGHT OF A TIN HYDROCARBON COMPOUND OF THE FORMULA RXAR4-XSN, IN WHICH R IS THE BUTYL RADICAL, AR IS THE PHENYL RADICAL, SN IS TIN, AND X IS A WHOLE NUMBER EQUAL TO 1 TO
 4. 